Abstract

Phosphogenesis is major sink for phosphorus (P) in the modern ocean, and the deposition of ancient phosphorites appears to have been an important sink for P in past oceans. To evaluate the importance of P burial, we combined published estimates (along with our data for one section of the Monterey Formation, California) of P inventories, areal extents, and time intervals of deposition for three well-studied major phosphorite deposits to calculate P accumulation and burial rates. Phosphorus accumulation and burial rates of major phosphorite deposits are comparable to those of the modern Peru margin. Though phosphorite deposition probably requires favorable sedimentological, tectonic, and/or oceanographic conditions, it does not appear to be a geochemically anomalous phenomenon when compared to modern oceanic conditions.